[SCSI] zfcp: Dont call zfcp_fsf_req_free on NULL pointer

Fix problem that zfcp_fsf_exchange_config_data_sync and
zfcp_fsf_exchange_config_data_sync could try to call zfcp_fsf_req_free
with a NULL pointer.

Reviewed-by: Martin Petermann <martin@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index fa896dc600b..a8e84065d00 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -1254,13 +1254,13 @@ int zfcp_fsf_exchange_config_data_sync(struct zfcp_adapter *adapter,
 
         spin_lock_bh(&adapter->req_q_lock);
         if (zfcp_fsf_req_sbal_get(adapter))
-                goto out;
+                goto out_unlock;
 
         req = zfcp_fsf_req_create(adapter, FSF_QTCB_EXCHANGE_CONFIG_DATA,
                                   0, NULL);
         if (IS_ERR(req)) {
                 retval = PTR_ERR(req);
-                goto out;
+                goto out_unlock;
         }
 
         sbale = zfcp_qdio_sbale_req(req);
@@ -1279,14 +1279,16 @@ int zfcp_fsf_exchange_config_data_sync(struct zfcp_adapter *adapter,
 
         zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
         retval = zfcp_fsf_req_send(req);
-out:
         spin_unlock_bh(&adapter->req_q_lock);
         if (!retval)
                 wait_event(req->completion_wq,
                            req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
 
         zfcp_fsf_req_free(req);
+        return retval;
 
+out_unlock:
+        spin_unlock_bh(&adapter->req_q_lock);
         return retval;
 }
 
@@ -1353,13 +1355,13 @@ int zfcp_fsf_exchange_port_data_sync(struct zfcp_adapter *adapter,
 
         spin_lock_bh(&adapter->req_q_lock);
         if (zfcp_fsf_req_sbal_get(adapter))
-                goto out;
+                goto out_unlock;
 
         req = zfcp_fsf_req_create(adapter, FSF_QTCB_EXCHANGE_PORT_DATA, 0,
                                   NULL);
         if (IS_ERR(req)) {
                 retval = PTR_ERR(req);
-                goto out;
+                goto out_unlock;
         }
 
         if (data)
@@ -1372,14 +1374,18 @@ int zfcp_fsf_exchange_port_data_sync(struct zfcp_adapter *adapter,
         req->handler = zfcp_fsf_exchange_port_data_handler;
         zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
         retval = zfcp_fsf_req_send(req);
-out:
         spin_unlock_bh(&adapter->req_q_lock);
+
         if (!retval)
                 wait_event(req->completion_wq,
                            req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
         zfcp_fsf_req_free(req);
 
         return retval;
+
+out_unlock:
+        spin_unlock_bh(&adapter->req_q_lock);
+        return retval;
 }
 
 static void zfcp_fsf_open_port_handler(struct zfcp_fsf_req *req)